I finally managed to play Syncopia in a venom SL (<3 Leungbok), and it took me ages to get working. I was mainly just selecting TDR<, pressing up and back down to reselect it before going to the ship screen and pressing O to go back and repeat. Eventually it said "Syncopia"

I tried again afterwards for rapier but I couldn't get it to work after a few minutes' worth of attempts, so I gave up. However, I imagine it should work with relatively high-ish frequency using the method in leungbok's video.